int IVsSelectionEvents.OnElementValueChanged(uint elementId, object oldValue, object newValue)
{
ThreadHelper.ThrowIfNotOnUIThread();
if (newValue is IVsWindowFrame frame &&
IsFrameElement() &&
IsDocumentFrame())
{
var textDocument = textDocumentProvider.GetFromFrame(frame);
if (textDocument != null)
{
OnDocumentFocused?.Invoke(this, new DocumentFocusedEventArgs(textDocument));
}
}
return(VSConstants.S_OK);
bool IsFrameElement()
{
return(elementId == (uint)VSConstants.VSSELELEMID.SEID_WindowFrame);
}
bool IsDocumentFrame()
{
return(ErrorHandler.Succeeded(frame.GetProperty((int)__VSFPROPID.VSFPROPID_Type, out var frameType)) &&
(int)frameType == (int)__WindowFrameTypeFlags.WINDOWFRAMETYPE_Document);
}
}
public ITextDocument FindActiveDocument()
{
ThreadHelper.ThrowIfNotOnUIThread();
// Get the current doc frame, if there is one
monitorSelection.GetCurrentElementValue((uint)VSConstants.VSSELELEMID.SEID_DocumentFrame, out var pvarValue);
if (!(pvarValue is IVsWindowFrame frame))
{
return(null);
}
return(textDocumentProvider.GetFromFrame(frame));
}
int IVsSelectionEvents.OnElementValueChanged(uint elementId, object oldValue, object newValue)
{
ThreadHelper.ThrowIfNotOnUIThread();
// Note: this notification can fire multiple times with different elementId value
// when the doc frame changes. Two cases:
// [ tool or doc window ] -> [ tool or doc window ] => elementId == SEID_WindowFrame
// [ doc window ] -> [ doc window ] => elementId == SEID_DocumentFrame
// We are only interested in the second case. See bugs #2079 and #2091.
if (elementId == (uint)VSConstants.VSSELELEMID.SEID_DocumentFrame)
{
ITextDocument activeTextDoc = null;
if (newValue != null && newValue is IVsWindowFrame frame)
{
activeTextDoc = textDocumentProvider.GetFromFrame(frame);
}
// The "active document" will be null if the last document has just been closed
ActiveDocumentChanged?.Invoke(this, new ActiveDocumentChangedEventArgs(activeTextDoc));
}
return(VSConstants.S_OK);
}